This paper presents the results of investigations carried out in the mid-south Tandilia mountain range, between the towns of San Manuel (Lobería District) and Barker (B. Juárez District). The archaeological research was focused on understanding the ways in which Pampean hunters-gatherers obtained raw material in the study area, especially in relation to the Sierras Bayas group ortho quarzites. Based on a series of systematic surveys, including analyses at various scales, evidence shows that the area of raw material procurement is significantly larger than was previously considered. In addition, possible new procurement modalities, previously unknown in the region, were identified.